<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>promise</title>
</head>
<body>
<script>
  let checkLogin = function () {
    return new Promise(function (resolve, reject) {
      let flag = document.cookie.indexOf("userId") > -1 ? true : false;

      if (flag = true) {
        resolve({
          status: 0,
          result: true
        })
      } else {
        reject("error");
      }
    })
  };

  let getUserInfo = () => {
    return new Promise((resolve, reject) => {
      let userInfo = {
        userId: "101"
      };
      resolve(userInfo);
    });
  };

  checkLogin().then((res) => {
    if (res.status == 0) {
      console.log("login success");
      return getUserInfo();
    }
  }).catch((error) => {
    console.log(`error:${error}`)
  }).then((res2) => {
    console.log(`userId:${res2.userId}`)
  });
  Promise.all([checkLogin(), getUserInfo()]).then(([res1, res2]) => {
    console.log(`result:${res1.result},result2:${res2.result})`);
  })
</script>
</body>
</html>
